1. Field of the Invention
The present invention is directed to a steel placement member for the placement and support of reinforcing steel in concrete structural members and, in particular, in concrete foundations and slabs.
An essential aspect of reinforced concrete design involves the accurate placement and support of reinforcing steel bars in a concrete structural member. It is crucial that the reinforcing steel be precisely located and supported an adequate distance inside the face of the concrete. Failure to maintain the reinforcing steel a sufficient distance inward of the face of the concrete results in undesirable oxidation of the steel, necessitating very costly and extensive restoration of the structural member. The steel placement assembly of the present invention overcomes the problem of oxidation by accurately locating the steel reinforcement the optimum distance inside the concrete face.
The integrity of a concrete structural member is further determined by how effectively the reinforcing steel bars are maintained in position within the concrete form to prevent unwanted shifting of the steel when the concrete is placed. Despite the best efforts of construction personnel to place and hold reinforcing bars within the concrete form, the forces realized while placing the concrete inevitably shift the steel from its specified position or cause failure and deformation of the steel supporting devices.
As a result, Code-specified dimensions for concrete cover are negated, with future costly corrective and restorative work a probable consequence. The inability of present steel placement devices to accurately attain code specifications results, additionally, in approval delays which seriously undermine the budget and schedule allocated for a particular construction project. Even more critically, the deterioration arising from improperly located steel reinforcement is apt to cause dangerous structural damage which creates serious liabilities for the builder, engineer and architect.
The subject steel placement member prevents undesirable movement or shifting of the steel from design parameters and thereby enhances the ability of architects and engineers to design more efficiently. The attributes in design and placement of the reinforcing steel realized through utilization of the instant invention result in lower costs of construction and maintenance for reinforced structural members. The present steel placement member provides a fast, easy and inexpensive means for maintaining the integrity reinforcing steel, both during construction and for the life of the structural member.
More specifically, the present invention provides a steel placement member which positively supports and locates a reinforcing steel bar the required distance inside the face of the concrete and above the foundation pad. The subject steel placement member is uniquely capable of securing the steel reinforcing bars against lateral and rotational movement. The steel placement member is formed to accommodate reinforcing steel bars of diverse sizes, being color-coded according to steel size to allow for quick and easy identification in the field. Further, the steel placement member is integrally molded of styrene and/or polyethylene in a manner conducive to mass-production at relatively low cost. Capable of supporting a reinforcing steel bar firmly, the steel placement member is able to withstand the pressures imposed during placement of the concrete without damage or failure and is durable enough that construction personnel may walk upon the reinforcing mate to set dowels or bolts or perform other required procedures. Moreover, the steel placement member is light in weight, is easy to carry and transport, and is suitable for storage in bulk amounts until needed.
Finally, because a portion of the steel placement member remains visible after the forms are removed, it is possible to supervise and inspect its proper use during construction, immediately and even years later. The color-coding system allows builders, architects and engineers to verify that the correct size of reinforcing steel bar was utilized, thereby providing a built-in assurance of quality for the life of the reinforced concrete structural member.
2. Prior Art
Several prior art patents are directed to supports or chairs for concrete reinforcing members. For example, U.S. Pat. No. 4,060,954 discloses a bar chair comprising a body member having tubular depending legs which snap onto the upwardly extending outer stads provided on the upper surface of an identical body member. Inside studs on the upper surface of each body member cooperate with the outer studs to retain various sizes of reinforcing bars.
U.S. Pat. No. 2,194,834 discloses a reinforced concrete stool comprising an upper section which fits over a lower section that has formed therein a notch for receiving a reinforcing rod. Similarly, U.S. Pat. No. 1,672,852 shows a support for a concrete reinforcing member consisting of a flat base and an upright body having a bifurcation in its upper end and for supporting a reinforcing member in proper relation.
Components for the horizontal and vertical spacing of tubular members are also known in the prior art. U.S. Pat. No. 3,464,661 is directed to a conduit spacer apparatus comprising identical spacer members which mate to form a plurality of recesses for retaining tubular conduit. Each spacer is provided with upwardly projecting tongues and downwardly opening tongue receiving receptacles. The upwardly projecting tongues of one spacer member are inserted into the receptacles of the spacer member to which it mates.
None of the prior art patents discloses an apparatus which is capable of effectively positively locating and supporting reinforcing steel against both lateral and rotational movement and a desired distance within the face of the concrete, while withstanding the force and stress imposed during concrete placement. Furthermore, the prior art fails to provide a device which accurately locates the reinforcing steel to prevent undesired movement while the concrete is being placed and which is, simultaneously, field-adaptable. The present invention accomplishes the foregoing objectives while being adaptable to produce structural members of various sizes which are subject to diverse reinforcement specifications and requirements, and while being easy, cost-effective and convenient to use.